This invention relates to an electronic musical instrument having a pan-pot function.
When a musical tone signal generated from a musical tone generator is transmitted to two VCAs (voltage controlled amplifiers) and two musical tone signals which are output from these VCAs are transmitted to two loudspeakers which are separated, musical sound is heard as if it were generated from the intermediate position between the two loudspeakers if the ratios of the levels of such musical tone signals obtained from the VCAs are set to 1:1. On the other hand, if the ratio of the output levels of two VCAs is set to, for example, 7:3, the musical sound is stronger in the direction of the loudspeaker with the musical tone signal corresponding to 7. In this way, the method for hearing the musical sound from a predetermined position between two loudspeakers by properly setting the volume ratios of the musical sounds to be generated from two loudspeakers can be accomplished and is known as pan-pot. In conventional electronic musical instruments, a method exists of performing pan-pot by controlling the two VCAs by providing two volume control signals which are generated from a single control voltage generator and the mutual level ratios are kept constant. In addition, there is also a method of accomplishing the pan-pot in which one volume control signal is selectively generated from a plurality of control voltage generators to control two VCAs using this volume control signal.
However, both of the above conventional sound image localization systems or pan-pot systems have no appeal to electronic musical instrument users, since the sound image can not be localized freely and correctly at a fixed location, and sound variation is poor.